About

Leon Shterengas is a Professor at the Department of Electrical and Computer Engineering at Stony Brook University. His research focuses on high power and high speed light emitters, carrier dynamics in nanostructures, and molecular beam epitaxy. His work involves exploring the fundamental properties and applications of light-emitting devices, contributing to advancements in optoelectronics and nanotechnology.

Research topics

• Optics
• Optoelectronics
• Materials science
• Physics
• Chemistry

Selected publications

• Epitaxial growth of low density InAs/GaAs quantum dots emitting in 1.3-1.6µm range

  2026-03-05

  articleSenior author
  PublisherDOI

• Midinfrared Semiconductor Photonics – A Roadmap

  2025-11-17

  article

  <p dir="ltr">Semiconductor photonic devices operating in the midwave infrared (mid-IR, which we roughly define here as wavelengths spanning 3 to 14 µm) uniquely address a wide range of current practical needs. These include chemical sensing, environmental monitoring, industrial process control, medical diagnostics, thermal imaging, LIDAR, free space optical communication, and security monitoring. However, mid-IR device technologies are currently still works in progress that are generally much less mature than their near infrared and visible counterparts. Not only are most of the relevant materials more difficult to grow and process, but attainment of the desired optical device performance is often fundamentally more challenging. This Roadmap will review the leading applications for mid-IR optoelectronics, summarize the status and deficiencies of current device technologies, and then suggest possible roadmaps for improving and maturing the performance, manufacturability, and cost of each device type so the critical needs that are uniquely addressed by mid-IR photonics can be satisfied.</p>

  PublisherDOI

• Midinfrared Semiconductor Photonics – A Roadmap

  2025-11-17

  article

  <p dir="ltr">Semiconductor photonic devices operating in the midwave infrared (mid-IR, which we roughly define here as wavelengths spanning 3 to 14 µm) uniquely address a wide range of current practical needs. These include chemical sensing, environmental monitoring, industrial process control, medical diagnostics, thermal imaging, LIDAR, free space optical communication, and security monitoring. However, mid-IR device technologies are currently still works in progress that are generally much less mature than their near infrared and visible counterparts. Not only are most of the relevant materials more difficult to grow and process, but attainment of the desired optical device performance is often fundamentally more challenging. This Roadmap will review the leading applications for mid-IR optoelectronics, summarize the status and deficiencies of current device technologies, and then suggest possible roadmaps for improving and maturing the performance, manufacturability, and cost of each device type so the critical needs that are uniquely addressed by mid-IR photonics can be satisfied.</p>

  PublisherDOI

• Midinfrared Semiconductor Photonics - A Roadmap

  ArXiv.org · 2025-11-05 · 1 citations

  preprintOpen access

  Semiconductor photonic devices operating in the midwave infrared (mid-IR, which we roughly define here as wavelengths spanning 3 to 14 microns) uniquely address a wide range of current practical needs. These include chemical sensing, environmental monitoring, industrial process control, medical diagnostics, thermal imaging, LIDAR, free space optical communication, and security monitoring. However, mid-IR device technologies are currently still works in progress that are generally much less mature than their near infrared and visible counterparts. Not only are most of the relevant materials more difficult to grow and process, but attainment of the desired optical device performance is often fundamentally more challenging. This Roadmap will review the leading applications for mid-IR optoelectronics, summarize the status and deficiencies of current device technologies, and then suggest possible roadmaps for improving and maturing the performance, manufacturability, and cost of each device type so the critical needs that are uniquely addressed by mid-IR photonics can be satisfied.

  PublisherOA PDFDOI

• Mid-infrared GaSb-based SAM APD with hole-initiated multiplication

  Applied Physics Letters · 2025-10-06

  articleSenior author

  The III–V-Sb separate absorption and multiplication (SAM) avalanche photodiode (APD) devices optimized for hole-initiated impact ionization have been developed. The hole-initiated process was selected to benefit from minimal valence band offset between InAsSb absorber and AlGaAsSb multiplier sections. The heterostructure design of the device facilitated shallow mesa fabrication, thereby minimizing etched sidewall leakage current. We tested devices with varying widths of the multiplier sections, with the most effective performance observed in SAM APDs featuring a 300 nm-thick multiplier section. The devices had cutoff wavelength of ∼3.9 μm at 80 K and operated in a background limited regime up to ∼200 K. The avalanche breakdown voltage was approximately −17.7 V at 80 K, increasing with temperature at a rate of 9.7 mV/K. An efficient hole-initiated impact ionization process resulted in multiplication gain values nearing one thousand, leading to peak values of current responsivity exceeding 50 A/W. It was observed that extensive tunneling occurs within the bias range between punch-through and avalanche breakdown, presumably due to the penetration of the electric field into the narrow bandgap absorber.

  PublisherDOI

• Carrier recombination in MBE grown InGa0.2AsSb0.27 and InAsSb0.09 alloys lattice-matched to GaSb for mid-wave infrared device applications

  Applied Physics Letters · 2025-07-28 · 1 citations

  articleSenior author

  This study presents the molecular beam epitaxy growth of the indium-rich InGa0.2AsSb0.27 alloy with a 0.26 eV bandgap, lattice-matched (LM) to GaSb. A significant finding is the high material metrics, particularly the minority carrier lifetime (0.3 μs) and the background carrier concentration (8 × 1015 cm−3), in which the product reaches half the value of the reference InAsSb0.09 alloy. This indicates the suitability of indium-rich InGaxAsSby alloys LM to GaSb for low-dark-current, high-quantum-efficiency detectors for the entire mid-wave infrared wavelength range.

  PublisherDOI

• Photonic Crystal Surface Emitting GaSb-Based Type-I Quantum Well Diode Lasers

  IEEE Journal of Selected Topics in Quantum Electronics · 2024-08-05 · 2 citations

  articleOpen access1st authorCorresponding

  The GaSb-based epitaxially regrown monolithic diode PCSELs operating near 2 μm at room temperature in continuous wave regime and generating 30 mW of output power from 200 μm diameter aperture have been designed and fabricated. The devices demonstrated CW threshold current density of about 500 A/cm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>. The laser output power was enhanced thanks to increased buried void area fill-factor in the photonic crystal layer with multiple voids per unit cell. The PCSEL generated ultra-low divergence donut shape beams at the currents near threshold. At higher injection currents, the device brightness was limited by excitation of the higher order lateral modes. Generation of the vector-vortex beams of different types by different band edge states of the buried photonic crystal was observed.

  PublisherOA PDFDOI

• Continuous wave room temperature operation of the GaSb-based photonic crystal surface emitting diode lasers

  2024-03-12 · 1 citations

  article1st authorCorresponding

  We report on the continuous wave (CW) room temperature operation of epitaxially regrown monolithic GaSb-based photonic crystal surface emitting diode lasers (PCSEL) with &lambda; &asymp; 2 &mu;m. The devices are based on laser heterostructure containing carrier stopper layer designed to inhibit electron leakage into buried photonic-crystal section. Atomic hydrogen cleaning of the nanopatterned surface followed by optimized epitaxial step resulted in highly uniform airpocket-retaining regrowth. The increase of the number of air-pockets in unit cells of the buried photonic crystal layer led to enhancement of the PCSEL output power and improvement of the far field pattern The PCSELs with buried high-index-contrast photonic crystal utilizing four air-pockets per unit cell generated 30 mW of continuous wave power from 200 &mu;m diameter aperture.

  PublisherDOI

• Amplification of GaSb-Based Diode Lasers in an Erbium-Doped Fluoride Fibre Amplifier

  IEEE photonics journal · 2023-01-19 · 2 citations

  articleOpen access

  Building upon recent advances in GaSb-based diode lasers and Er-doped fluoride fibre technologies, this article demonstrates for the first time the fibre-based amplification of mid-infrared diode lasers in the wavelength range around 2.78 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\mu$</tex-math></inline-formula> m. The laser setup consists of a GaSb-based diode laser and a single-stage Er-doped fibre amplifier. Amplification is investigated for continuous wave (CW) and ns-pulsed input signals, generated by gain-modulation of the GaSb-based seed lasers. The experimental results include the demonstration of output powers up to 0.9 W, pulse durations as short as 20 ns, and pulse repetition rates up to 1 MHz. Additionally, the amplification of commercial and custom-made GaSb-based seed lasers is compared and the impact of different fibre end-cap materials on laser performance is analysed.

  PublisherOA PDFDOI

• Continuous wave room temperature operation of the 2 <b> <i>μ</i> </b>m GaSb-based photonic crystal surface emitting diode lasers

  Applied Physics Letters · 2023-03-27 · 7 citations

  articleOpen access1st authorCorresponding

  Continuous wave room temperature operation of 2 μm GaSb-based photonic-crystal surface-emitting diode lasers has been realized. The deep etched square mesa devices showed threshold current densities of 500 A/cm2 at 20 °C. The epi-side down mounted lasers generated above 10 mW of output power in the continuous wave regime and tens of milliwatts in pulses from the 200 × 200 μm2 aperture. The breakthrough in the device performance parameters was achieved thanks to a highly homogeneous air-pocket retaining epitaxial regrowth process optimized for a specifically designed antimonide diode laser heterostructure. The nanofabrication method utilizing low temperature atomic hydrogen surface cleaning yielded low disorder square lattice of droplet-shaped voids covered by uniform p-cladding layer. The laser emission spectrum as well as near/far field patterns demonstrated peculiar features presumably linked to deformation of the void shape during regrowth and formation of the array of filaments.

  PublisherOA PDFDOI

Recent grants

• Collaborative research: Compact room temperature operated THz emitters with scalable architecture and low electric power consumption

  NSF · $331k · 2017–2021

• GOALI: Widely Tunable Gasb-Based Diode Lasers for Spectroscopy

  NSF · $409k · 2014–2018

Frequent coauthors

• Gregory Belenky

  Stony Brook University

  440 shared

• G. Kipshidze

  Stony Brook University

  282 shared

• Takashi Hosoda

  Kyoto University

  195 shared

• Sergey Suchalkin

  Stony Brook University

  79 shared

• D. Donetsky

  Stony Brook University

  65 shared

• Tao Feng

  Stony Brook University

  37 shared

• David Westerfeld

  Stony Brook University

  35 shared

• Aaron Stein

  Brookhaven National Laboratory

  35 shared

Labs

• Electrical and Computer EngineeringPI

Education

• Ph.D., Electrical Engineering

  University of California, Los Angeles

  1989

• M.S., Electrical Engineering

  University of California, Los Angeles

  1985

• B.S., Electrical Engineering

  University of California, Los Angeles

  1983